Process of treating ores.



, Wh -H1 MM A. LOGKWOOD & M. R. A. SAMUEL.

PROCESS OF TREATING ORBS.

APPLICATION nun JAN. 11, 1909.

956,381 Patented Apr. 20,1910.

Wi Z71 video sTA'i s PATENT (OFFICE.

ALFRED Anrnnn LocxwooD AND mAEcUs REGINALD ANTHONY SAMUEL, 01 mm DoN,ENGLAND, ASSIGNOBS TO THE MUEEX SYNDICATE, LIMITED, or LoNDoN,

ENGLAND.

Specification of Letters Patent.

i Application filed January 11, 1909. Serial No. 411,716.

Patented Apr. 26, 1910.

their constituents owing to then physicalformation. This ditficulty isusually caused by the pseudomorph formation of the ore; this is the casefor examplein complex lead and zinc'ores such as Broken Hill ores.

Accordin to this invention crushed ores, under whic term it is intendedto include tailings, middlings or concentrates, are sub- Asa comparativeexample of the treat-- jected to a preliminary treatment of agitationwith a reagent or reagents in such a manner that the lncrustations aresufliciently attacked to free the metallic particles so that they can beclassified b any known means. In some cases improve results may beobtained by first heating the ore or the like to a temperaturepreferably just below that of desulfurization. As reagents there areemployed solutions of substances such as caustic alkali or sodium orpotassium silicate which may be used either separately or in succession'or in combination according to the ore to be treated. The quantity ofthe reagent and water necessary and the length of t1me' required for thetreatment will di er more or less according to the ore to be treated, itshould be such that the incrustations are loosened while the metalsremainundissolved.

ment, a parcel of 2 tons of Broken Hill pro :prietary ore of a verycomplex formation ;was taken and crushed to about 40 mesh to the linearinch. 2,240 lbs. of this was treated with a solution containing about 5%merits, which wil profitable to treat the whole first, or to treat ofcaustic soda and 1% of silicate of soda in the proportionof 25 lbs. ofthe solution to each 100 lbs. of ore. After a 'tating for about 3Qminutes, the pulp was ed onto sizin screens and thence assed to avanning ta le. The result of this treatment was as follows, the scale ofthemesh to the linear inch being 60 and 80 :103% lbs. .of coarse (plus60) galena (dried), 172 lbs. of fine lus 80 and minus 80) galena and 43%lbs. 0 zinc lead middlings from the coarse and 36glbs. middlings fromthe fine. The assay value of thegalena was 76.8% lead with 3.9% zinc andthe middlingscontainedfree galena and free blende. The remaining mannerincluding the agitation for 30 minutes with water but without theaddition of 2240 lbs. of the ore was treated in-the same caustic orsilicate. The result was 88 lbs.

value of the galena was 72 lead-with 6.5% zinc while the middlingsappeato be quite inseparable and further crd ing would have been required tofree themetallic particles from one another. i

' It is quite obvious that the treatment may I it be applied as in theexample 'to ithe ore in bulk or the metallic particles concentrated byan oil or similar selective process and then treated and classified .orof course the crushed ore may and passed over the table before treatmentgettin as much free galena as possibla. then taking off the table fortreatment a large line of middlings containing. the 'incrustedparticles. These middlings are then'treated as before described andpassed over a table or otherwise classified. The particular method oftreatment to be adopted will easily be found bythe aid of a fewexperiwhether itis more the middlings, or the eoncentrates'or tailintogether or separately.

%\ lace of using caustic soda direct it and ment of ores but not in ofores which have undergone a selective process in which oils, soaps orthe like have been used as the liquid and which even after treatment byknown means (such as with soap emulsion or an alkaline emulsifying agentor by roastingg are still in an imperfect state for classl cation, aretreated as herein before described with a reagent or reagents accordingto, the ore to be treated. The silicates 'of sodium or otassium areespecially suitable for zinc ead concentrates may conveniently be addedsimultaneously with the emulsion or the like, agitation being necessaryin all cases. Such treat ment not only frees the ores from theirincrustations as before but also overcomes or prevents the acquiredtendency of the particles to adhere together due to variouscircumstances dependent on the liquid used whether oil, mineral oil orsoap. The action of sodium or potassium silicate however when used aloneis somewhat slow,.preferably they are used in admixture with caustic,

alkali. n addition to freeing ores from incrustations the use of sodiumor potassium silicates has the further, advantage of precipitating anysoluble salts present, thus preventing the water used from becomingsick.

It is to be understood that it is not desired by this treatment todissolve ,the metals, exceptpossibly to a very slight degree, but merelyto loosen the incrustations and to remove them by an abrasive treatmentwith a reagent, usually in the cold.

In dealing with ores for treatment, a few tests will be necessary toascertain the degree of fineness to which they should be crushed beforetreatment and this will vary with the formation of the ore and may alsobe varied to suit the particular method of concentration to be employed,but speaking generally the ore should be left as coarsely crushed aspossible and this for two reasons, viz: in order to reduce the amount ofslimes formed and because of the decreasing advantage of such atreatment, for it will be obvious that with a pulverized ore theincrustations will no longer be present and the more finely the ore iscrushed the more the incrustations will be broken down and the less needthere will be for the treatment except when overcoming or preventing theacquired'tendency of particles to adhere together when the ore istreated with oilsor the like.

We are aware that the substances mentioned have before been used in thetreata manner to produce the same results.

We are also aware that gold ores have been treated with a heatedsolution of a soluble silicate and with a soluble silicate and caustipalkali under pressure and we do not claim t is.

In the drawing A is a vessel provided with an agitator a.

B is a sizin screen, B a second and finer screen inclin in oppositedirection to the first. The combined screens are directly connected tothe piston of a reciprocating engine b.

b, b are delivery spouts.

The coarse and the finer ore is treated on a vanning table .at differenttimes. As shown the finer ore is delivered onto a vanning table.

C is a vanning table supported pn springs c and reciprocated by means ofan eccentric c.

0 indicates means for supplying water to the table and 0 indicates achute into which the heavier parts fall.

What we claim is e 1. The herein described process of treating sulfidores, which consists in crushing ores composed offriablesulfids in whichthe commingled grains or particles are bound together by a sulfid,agitating such crushed ores with an alkaline silicate solution to weakenthe bonds between the grains of the commingled sulfids on cleavage linesso that they may be advantageously separated without excessive grindingand concomitant sliming and then subjecting said particles to separationand separate collection.

2. The herein described process of treating sulfid ores which consistsin coarsely crushing ores composed of friable sulfids in which thecornmihgled grains or particles are incrusted and which are boundtogether by a sulfid, agitating such crushed ores with an alkalinesilicate solution to weaken the bonds between the grains of thecommingled sulfi ds on cleavage lines and to free the metalliferousparticles but not to dissolve or appreciably change the nature of eitherthe said metalliferous particles or other particles with which they areassociated, and then subjecting said particles to separation andseparate collection.

3. The herein described process of treating ores, which consists incrushing incrusted zinclead ores in which metalliferous particles areagglomerated by nature, agitating such crushed incrusted zinc lead oreswith analkaline silicate solution in a manner adapted to free themetalliferous particles but not to dissolve or appreciabl change thenature of either the said metal iferous particles or the other'saidparticles with which they are associated, and then subjectin saidparticles to separation and separate collection.

4. The herein described process, which consists 1n coarsely crushingincrusted zinc lead ores in which metalliferous particles are saidmetalliferous particles or the other said 10 particles with which theyare associated, and then subjecting said particles to separationagglomerated by nature, agltating such and separate collection.

crushed incrusted zinc lead ores with an. .alkaline silicate solution ofa compound of a metal of at least 4% strength to free the metalliferousparticles but not to dissolve or appreciably change the nature of eitherthe ALFRED ARTHUR LOGKWOOD.

MARCUSREGINALD ANTHONY SAMUEL. \Vitnesses:

ALFRED WRIGHT,

JOSEPH ANTHONY YeLEsIAs.

